stainless bolt properties 4

[yarsky]

For some reason we need to design a hanger-type support using stainless steel bolts. However, finding an information regarding stainless steel bolts (rods) tensile strength proved to be a problem. Could anybody provide us with some info or direct to a good source?
Thank you.

 

[metengr]

Could you provide some additional information regarding your specific application - environment, service temperature, etc? The optimum selection of a suitable stainless steel bolt material would be based on this information.

 

[BATman2]

Yarsky,

Start with the following link:

http://mdmetric.com/fastindx/t28u.pdf

I suggest you follow Metengr's comment regarding grade selection.

Also, check the Industrial Fasteners Institute (IFI) manual Inch Fastener Standards There is a section on Corrosion medium vs. materials and plenty of mech. data. Also see ASTM F593.

SST also has a higher thermal expansion that plain carbon steel. You may need to consider that. Keep in mind that stainless fasteners tend to gall. If this is a joint that will be frequently maintained, tightened, etc. anti-seize compound is recommended.

Batman 2

 

[yarsky]

This hanger is part of railroad bridge repair. It is open to elements, but closed for inspection - that is why the client wants it to be corrosion resistant. Apart for that there are not any special environmental conditions I know of.
Thanks for your reply.

 

[MikeHalloran]

I recommend anti-seize even for a stainless fastener that will be spun down and wrenched only once.



Mike Halloran
NOT speaking for
DeAngelo Marine Exhaust Inc.
Ft. Lauderdale, FL, USA

 

[metengr]

If you need a specific bolt specification, I would use ASTM A 320, Class 1A, Grades B8 or B8A (304) or B8LN (304N).... The Class 1 A fasteners are supplied in the solution treated condition for maximum corrosion resistance. The ASTM A 320 Specification provides minimum mechanical property requirements for your application.

Make sure the anti-seize compound is compatible for use on austenitic stainless steel fasteners.

 

[ccw]

Hi Yarsky,
If this application is safety related load bearing, beware of counterfit bolts and bolts from sources that have obfuscated paperwork or paperwork promised but never delivered. This is particularly annoying if there is a failure later on.

 

[Paskenell]

Hi Yarsky,

There are two popular ASTM specs on stainless steel bolts, where parts are readily available. ASTM A193 and ASTM F593.

http://www.ssina.com/download_a_file/fasteners.pdf

is a free dowloand that will give you basic info on both, including tensile.

I am not familiar with railroad bridge construction, but on a road bridge, where road salt could be present, the use of 304 stainless should be tested by a corrosion engineer and likely, discouraged. Salt and stainless (chloride) don't play well together.

As stated by Yarsky, stainless bolts are not covered by the new Fastener Law. Request good documentation up front and while I can't imagine anyone would be stupid enough to still be providing counterfeit stainless bolts, here is a photo on some to be on the look out for

https://sbms.pnl.gov/standard/2t/2t03e010.htm.

Any ASTM certified stainless bolt with the two dash marks on it (as seen on forementioned page) is bogus. The two dash marks reflect the bolts was originally made as 18-8 commercial only.